From 4b7ff33c2693438c22b5ca31985a7d41d3cf631e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Thu, 11 Mar 2010 22:03:49 +0000
Subject: [PATCH] options: Learn how to merge identical integer values.

svn path=/nixpkgs/trunk/; revision=20581
---
 pkgs/lib/options.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/lib/options.nix b/pkgs/lib/options.nix
index 2c5e7aa208d5..edcbfaa48305 100644
--- a/pkgs/lib/options.nix
+++ b/pkgs/lib/options.nix
@@ -195,6 +195,8 @@ rec {
     else if all isAttrs list then fold lib.mergeAttrs {} list
     else if all builtins.isBool list then fold lib.or false list
     else if all builtins.isString list then lib.concatStrings list
+    else if all builtins.isInt list && all (x: x == head list) list
+         then head list
     else throw "Cannot merge values.";
 
   mergeTypedOption = typeName: predicate: merge: list: